What if...? #suggestion

Glyphs
1

Let’s say:

  1. Light Master has a side bearing of 80 for the H.
  2. I create a Bold master and tell the Bold master that its side bearing should be 75% of the Light master.

Would save quite much time!

2

Relative sidebearings are not as useful as they appear (e.g. glyphs with a negative sidebearing will become wider). I would recommend an absolute shift applies with Glyphs > Transform Metrics.